In taking over Scott Burns' column, I promised to perform some money magic — to show you ways to better manage your finances and safely raise your living standard.

I can't do it one-on-one. But let me point you to an online tool, called ESPlannerBASIC, that can help perform an array of money miracles. My company, Economic Security Planning Inc., provides this tool for free.

Full disclosure: The tool is free, but if you want to save your data on the site, it costs $40, or $80 with advanced features.

Let me illustrate ESPlannerBASIC through the story of a pretend couple.

Meet the Smiths

Meet John and Jane Smith, a married California couple, both age 50. John and Jane have neither children nor parents to support. They think they are in good financial shape — good enough to retire at 60. They both earn $50,000, and each of them has $200,000 in 401(k) accounts to which they contribute $1,500 a year with an equal-sized employer match. They also have $50,000 each in Roth IRAs and $250,000 each in nonretirement account assets.

The Smiths plan to start withdrawing smoothly from their retirement accounts at 60 and take Social Security at 62. Their $500,000 house, which they don't plan to sell, has a 30-year, $300,000 mortgage with a monthly $1,400 payment. Other annual housing expenses total $10,000.

The Smiths are counting on earning 2 percent above inflation, which they forecast at 3 percent, on their savings. Both plan to live to 100 because they might.

Finally, when they retire, the Smiths expect to pay $15,000 a year for health insurance and out-of-pocket health costs.

Now that you've met the Smiths, let me ask you a question. Assuming nothing unexpected happens, how much can they spend this year, after covering their fixed expenses and taxes, assuming they want to spend the same amount for the following 49 years? This is a really tough question.

Calculating how much the Smiths can "spend till the end" (Scott and I wrote a book with this title) involves lots of interconnected factors. The list includes federal taxes, California taxes, Social Security benefits, Medicare Part B premiums, time-varying housing costs, inflation and retirement account withdrawals.

Your brain, my brain or any human brain could spend eternity and still not get the right answer. But ESPlannerBASIC can do so in half a second. That's magic.

So what's the answer? It's $28,202. This is the amount, measured in today's dollars, that the Smiths can afford to spend every year for the next 50 and cover all their other commitments. But gee, doesn't $28,202 seem very low, given that the Smiths make $100,000 a year and have $1 million in assets? Actually, no, and here are three reasons why.

First, they need to pay for themselves for the next half-century; second, $400,000 of their assets are taxable — the two 401(k) accounts; and third, they are retiring early. Indeed, they want to spend as much time retired as they spent working.

Now for some more bad news. The Smiths aren't saving anything apart from contributing to their retirement accounts. But they need, as ESPlannerBASIC shows, to save $22,705 this year and comparable amounts before 60 to maintain their living standard.

Time for some more magic. First, let's have the Smiths work through 65 and start Social Security and retirement withdrawals then. Phew! ESPlannerBASIC now lets them spend $40,347 a year on a discretionary basis. Yes, they'll have to work another five years, but so it goes if they want to maintain their current lifestyle.

Waiting till 70

But we can do better. Let's have them wait until they're 70 to take Social Security. Doing so raises their starting benefits by a whopping 42 percent. And their discretionary spending? It's now $43,155.

We're on a roll. Now let's have each Smith double their 401(k) contribution to save taxes. Bingo, they're up to $43,488 in annual discretionary spending.

Next, let's relocate them to Texas, which has no state income tax. Voila! We're up to $44,993. Finally, let's have the Smiths cut their housing costs in half since Texas has much cheaper housing. Jackpot — we're up to $56,890, more than double their initial discretionary spending level.

I could go on, but it's time for you to hang out at esplanner.com/basic. Just click Begin Planning at the bottom. Use it with your kids. Challenge them to help make you some money magic.

Laurence Kotlikoff is a Boston University economist and co-author of Get What's Yours. His company markets maximizemysocialsecurity.com. Readers can email questions to kotlikoff@economicsecurityplanning.com.